Do I require a gate driver IC to turn on my MOSFET BSS138, if I supply 12 V DC to the gate of the MOSFET?

The MOSFET is NOT being used to switch a PWM waveform. It is simply being used to turn on and off a relay. It will most probably be switched on once a day and once off a day. I have connected it has a low-side switch configuration.

Since 12 V DC at the input is sufficient to turn on the MOSFET I assume I will not need a gate driver IC, is this correct?

The relay coil is specified for a 24 V DC input.


simulate this circuit – Schematic created using CircuitLab

  • 1
    \$\begingroup\$ The only problem I see is how you are going to switch it on more times than you turn it off. \$\endgroup\$
    – tobalt
    Commented Nov 6, 2021 at 13:41
  • \$\begingroup\$ I deleted my comment about that because I didn't want to distract from the schematic but...I really hope it is not an editing artifact and there is an interesting answer behind it. But I think it is an editing issue. \$\endgroup\$ Commented Nov 6, 2021 at 14:22
  • \$\begingroup\$ I also deleted my comment because I did not read the datasheet details. \$\endgroup\$
    – Audioguru
    Commented Nov 6, 2021 at 14:47
  • \$\begingroup\$ @GTElectronics in deed that was an error \$\endgroup\$
    – JoeyB
    Commented Nov 6, 2021 at 14:55

1 Answer 1


The circuit is perfectly designed for your needs.

Just make sure your relay's coil draws less than 220mA (unlikely that it draws more but check).


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